次第だ — Depends On, It's Up To, That's Why

Meaning & Usage

次第だ (shidaida) is a versatile N2 grammar point. It primarily conveys that an outcome, nature, or reason depends on a preceding condition or action. This expresses a strong sense of contingency, indicating that something is determined by another factor. It can also serve to provide an explanation or reason for a situation, similar to "that's why," "it's due to the fact that...", or "the situation is such that...".

Consider making plans when a key factor is uncertain. For instance, you might say: 「旅行に行くかどうかは、お金かねがあるかどうか次第しだいだ。」 (Whether or not we go on a trip depends on whether or not we have money.) Here, 次第だ clearly marks "money availability" as the determining factor for the trip, establishing a direct causal link for the outcome.

In English, 次第だ can often be translated as "it depends on...", "it's up to...", "the outcome is determined by...", or "that's why/it's for this reason...". Generally, it's more formal than simple ～による (ni yoru) when expressing dependency. Moreover, it's more explanatory than simply stating a reason with ～から. It adds a nuanced layer of consequence or causality, giving weight to the preceding condition.

To truly grasp 次第だ, envision it as a linguistic "pivot point." Whatever immediately precedes 次第だ functions as this pivot or the determining factor. The situation or outcome thus pivots around this crucial element. When used for explanation, it acts as a concluding statement, summarizing the reason for a particular state of affairs. This often implies, "and so, that is the situation." Such usage is particularly valuable in formal reports or apologies where explaining circumstances is necessary.

This grammar point appears in both written and spoken Japanese. However, its slightly formal nuance means it's more common in structured conversations, presentations, and written documents. While simpler expressions might be preferred in very casual speech, 次第だ elevates the tone. It provides a more definitive statement of dependency or explanation, making it an excellent way to articulate complex dependencies or rationale concisely and politely.

Structure & Formation

The formation of 次第だ follows a few primary patterns. The core idea remains consistent: it attaches to the element that determines the outcome or provides the explanation.

1. Noun + 次第だ: This is a very common pattern where the outcome or nature is determined directly by the noun. It immediately follows the noun.

2. Verb (Plain form) + 次第だ: When used to provide an explanation, 次第だ can follow a verb in its plain (dictionary) form. This often indicates that the preceding action or state is the reason for the current situation. For the "depends on" meaning, the verb is usually part of a larger clause, such as "~かどうかは V(plain) 次第だ."

Here's a table summarizing the common structures:

It's important to note that while 次第だ can follow a plain verb form for explanations, for the "depends on" meaning, it typically connects to a noun or a more complex clause that itself implies dependency. An example is 「～かどうかはX次第だ」 (whether or not ~ depends on X).

Example Sentences

Decision Making & Outcome

Future Plans & Conditions

Explanations & Reasons

Personal Capability & Effort

Common Mistakes

Mistake 1: Confusing with 「V-masu + 次第」 (as soon as)

❌ 駅えきに着つき次第しだい、連絡れんらくします。

✅ 駅えきに着ついたら、すぐに連絡れんらくします。

Explanation: This is a very common mistake for learners. While 次第 can indeed mean "as soon as" (Verb-masu stem + 次第), that usage has a distinct meaning and grammatical structure. When expressing "depends on" or providing an explanation, the common patterns are Noun + 次第だ or a clause + 次第だ. The example incorrectly uses Verb-masu stem + 次第だ to convey "as soon as I arrive, I'll contact you." This idea is more naturally expressed with 「～たら、すぐに」 or 「～次第」 without だ (and a different nuance). When discussing dependency or explaining a situation, always adhere to the Noun/Clause + 次第だ structure.

Mistake 2: Overusing when a simpler phrase suffices

❌ 私わたしの気持きもち次第しだいで行いきます。

✅ 私わたしの気持きもちによる。

Explanation: While not grammatically incorrect, using 次第だ can sometimes sound overly formal or slightly dramatic if a simpler expression like ～による (ni yoru - depends on) would be more appropriate, especially in casual conversation. 次第だ typically implies a stronger sense of determination or consequence. Reserve 次第だ for situations where you want to emphasize that an outcome is truly determined by something, or to offer a formal explanation for a situation.

Mistake 3: Incorrectly attaching to verbs

❌ 行いく次第しだいだ。

✅ 行いくかどうかは状況じょうきょう次第しだいだ。

Explanation: When 次第だ follows a verb to express the "depends on" meaning, it usually needs to be part of a larger conditional clause. For example, 「～かどうかは V（plain）+次第だ」 is a common construction. Simply attaching 次第だ directly to a plain form verb, like 「行く次第だ」, often sounds unnatural. Exceptions include the "as soon as" usage (V-masu stem + 次第) or more complex explanatory sentences where the verb describes the reason (e.g., 「～した次第だ」). Remember, the "depends on" meaning typically requires the determining factor to be a noun or a complete conditional clause.

Mistake 4: Missing the essential "だ" or its polite forms

❌ 結果けっか次第しだい。

✅ 結果けっか次第しだいだ。

Explanation: 次第だ functions as a complete predicate. Therefore, it often requires the copula だ (or its polite forms です/でございます) at the end of the sentence to form a complete thought, especially when stating a fact or conclusion. While だ can sometimes be omitted in very casual speech, it is generally safer and more grammatically correct to include it, particularly in written Japanese or more formal contexts. Without it, the sentence can feel incomplete or like a fragment, similar to ending an English sentence with a preposition.

Cultural Notes

In Japanese culture, the idea that things "depend on" or are "up to" certain factors is deeply ingrained. This reflects a recognition of external circumstances and collective considerations. 次第だ captures this sentiment elegantly. It allows speakers to express conditions or justifications without sounding overly assertive or assigning sole blame, which aligns with the Japanese preference for indirect communication and harmony. It emphasizes that outcomes are frequently the result of interconnected elements.

You will often encounter 次第だ in business settings or formal announcements. For example, a company might state, 「今後こんごの対応たいおうは、お客様のご意見ごいけん次第しだいとさせていただきます」 (Our future response will be decided based on our customers' opinions). This phrasing sounds polite and professional, highlighting that the decision will be made with due consideration of external factors, rather than unilaterally.

It's also used to convey personal responsibility or agency, as in 「将来しょうらいはあなた次第しだいだ」 (Your future is up to you). This common phrase encourages individuals to take charge of their destiny, recognizing that individual effort is a determining factor. The explanatory usage is also frequently heard in apologies or explanations for past situations, providing context in a polite and often humble manner.

Mastering the proper usage of 次第だ enables you to communicate dependencies and reasons with a level of formality and nuance that resonates well with native speakers. It is a valuable phrase for both understanding and producing sophisticated Japanese, helping you navigate both casual and formal interactions effectively.

JLPT Tips

For the JLPT N2 exam, mastering 次第だ is crucial as it frequently appears in reading comprehension and grammar sections. Pay close attention to its context. At this level, the primary meaning will likely be "depends on" or "it's up to," but the explanatory "that's why/it's due to" meaning is also vital for comprehensive understanding.

Distinguish carefully from 「V-masu + 次第」: This is the most common pitfall for learners. Remember that 「V-masu + 次第」 means "as soon as V happens" (e.g., 「準備じゅんびができ次第しだい、出発しゅっぱつします」 - As soon as preparations are complete, we will depart). While both share the word 次第, their meanings and grammatical functions are entirely different. Context will always clarify which one is being used. If an article describes a future outcome hinging on a condition, it's typically the "depends on" usage. If it's about immediate action after an event, it's the "as soon as" usage, which importantly, does not use だ at the end.

Look for the preceding element: Your strongest clue to differentiate the usages will be what comes directly before 次第だ. If 次第だ is preceded by a noun or a completed clause (e.g., a sentence ending with Verb-plain, Noun-da, Adjective-i, Adjective-na), it is highly likely to be the "depends on" or explanatory usage. If it is preceded by a verb stem (ます-form without ます), it is the "as soon as" usage.

Practice with varied examples: Ensure you understand how it attaches to different types of phrases and clauses. Pay attention to how the overall meaning of the sentence changes based on what comes before 次第だ. Reading various example sentences and attempting to rephrase them using similar grammar points like ～による or ～にかかっている can help solidify your understanding of its nuances and the subtle differences in formality and emphasis.

Context is king: Always read the full sentence and even the surrounding sentences. The JLPT often tests subtle nuances, and 次第だ has several. Understanding the overall situation and the speaker's intent will guide you to the correct interpretation, especially when choosing between similar-sounding grammar points.